Concurrent Processes and Their Syntax

A mathemaucal model of concurrent computaUon is presented Starting from synchronized commumcaUon as the only pnmitwe notion, a process is defined as a set of communication capabdmes The domain of processes is budt using the weak powerdomam construction of Smyth, which evolved from that of Plotkm A minimal set of operaUons for composing processes is defined These operations suggest a corresponding mmlmal syntax--the language offlowgraphs--m which to specify these composluons The concept offlow algebra is defined, processes and flowgraphs are examples of flow algebras Elsewhere it will be shown that flowgraphs are free (over a set of generators) in the category of flow algebras, here it is shown that processes are a flow algebra, and therefore constitute a suitable semantics for flowgraphs However, we emphasize that the nouon of flowgraph evolved from the notion of process and not the reverse.